Power distribution in a docking station

ABSTRACT

Docking stations that may facilitate the sharing or transfer of power among a portable computing device, a docking station, and an accessory. One example may provide power from an accessory to a portable computing device. Switches may be used to avoid harm from inadvertent contact with voltages on exposed terminals. Another example may provide power directly from a battery on a portable computing device to an accessory. Another may limit this direct connection to a first type of accessory. Examples may limit a power connection to another type of accessory through a regulator. Another example may power one or more internal circuits either through a portable computing device or an accessory, depending on a mode of operation of the portable computing device.

BACKGROUND

Portable computing devices, such as smartphones, music and videoplayers, and others have become ubiquitous. The features andcapabilities of these players have increased as well. As a result, thenumbers and types of accessory devices that these players maycommunicate with have grown at a remarkable rate.

At the same time, it may be desirable to have docking stations that maybe used to physically support these portable computing devices. Thedocking stations may support portable computing devices in asubstantially upright position. This may make it easy for a user toinsert and remove a portable computing device from a docking station andmay be a safer position for the portable computing device, as comparedto simply lying on a desktop or other surface where it may be morevulnerable to accidental damage.

It may also be desirable that the docking station provide a connectionbetween a portable computing device and a computer or other accessorydevice. Such a connection may allow data to be transferred between theportable computing device and the computer. This data may includevarious media, such as music, videos, photographs, and other data. Datamay be transferred from the portable computing device to the computer orfrom the computer to the portable computing device. Software orfirmware, or software or firmware updates may be transferred between theportable computing device and the computer as well.

It may also be useful if the docking stations are able to receive powerfrom a charger or other accessory and provide the power to chargebatteries in the portable computing devices. In still other situations,it may be desirable to provide power from a portable computing device toan accessory. Also, docking stations themselves may include circuitrythat may be powered from a portable computing device, accessory, orother source.

Thus, what is needed are portable computing device docking stations thatmay facilitate the sharing or transfer of power among a portablecomputing device, a docking station, and one or more accessories.

SUMMARY

Accordingly, embodiments of the present invention may provide portablecomputing device docking stations that may facilitate the sharing ortransfer of power among a portable computing device, a docking station,and one or more accessories.

In various configurations of embodiments of the present invention, powermay be provided by a portable computing device to one or both of adocking station and accessory, power may be provided by a dockingstation to one or both of a portable computing device and accessory, orit may be provided by the accessory to one or both of a docking stationand portable computing device. For example, the accessory may be acharger that receives power from a wall or car outlet and provides powerto a portable computing device via the docking station. In this example,power may be provided to the docking station by either the portablecomputing device or the charger accessory.

An illustrative embodiment of the present invention may provide adocking station where power may be provided by an accessory to aportable computing device. In this embodiment of the present invention,a wire, power conductor, or other conduit may be provided through thedocking station from a first connector arranged to mate with theportable computing device to a second connector arranged to connect toan accessory. This docking station may also be capable of providingpower from a portable computing device to an accessory. In thisembodiment of the present invention, a second wire, power conductor, orother conduit may be provided through the docking station from the firstconnector to the second connector.

In this illustrative embodiment, a voltage received from an accessory atthe second connector may appear at the first connector. When a portablecomputing device is not connected at the first connector, this voltagemay be present at terminals of the first connector where it may beinadvertently contacted by a user or a user's property. Accordingly,another illustrative embodiment of the present invention may provide aswitch or other circuitry in a power line between the second connectorand the first connector. When the switch or other circuitry detects thata portable computing device is not attached to the docking station, itmay open or otherwise be placed in a high-impedance state thereby eitherpreventing a supply voltage from being present on a terminal of thefirst connector, or current limiting any such supply voltage such thatharm is not likely to occur do to an inadvertent encounter.

Various embodiments of the present invention may provide power from aportable computing device to an accessory in various ways. For example,a docking station may directly connect an accessory to a battery of aportable computing device. In other embodiments of the presentinvention, this connection may be current limited or otherwise include aprotective circuit. For example, a low-dropout regulator may be placedin the docking station in line between the battery of the portablecomputing device and the accessory. In various embodiments of thepresent invention, the low-dropout regulator may be driven by thebattery directly or by a regulator, such as a buck-boost, shunt, orother type of regulator.

Various embodiments of the present invention may provide dockingstations having internal circuits. These circuits may be powered by aportable computing device, an accessory, or by another circuit eitherinside or external to the docking station. An illustrative embodiment ofthe present invention may provide a docking station having circuitspowered by a portable computing device. The power may be provided by abattery of the portable computing device through a regulator. To protectthe internal circuitry from power transients caused by fault or otherconditions, embodiments of the present invention may providecharge-storage capacitors at the inputs of the regulators. Disconnectdiodes may be included for further protection. To reduce powerconsumption in the docking stations, different circuits may be poweredby different regulators and these regulators may be turned off invarious states.

Embodiments of the present invention may provide docking stations thatmay connect to accessories using different types of connectorinterfaces. One such connector interface is the Lightening™ connectorinterface. This interface is reversible. That is a Lightening inset maybe interested into a Lightening receptacle in one of two orientations.Accordingly, an illustrative embodiment of the present invention mayprovide a docking station having a multiplexing circuit to detect anorientation of a connection to an accessory and to multiplex power anddata lines appropriately.

In an illustrative embodiment of the present invention, thesemultiplexers may be powered by a battery in the portable computingdevice. For example, these multiplexers may be powered by one or moreregulators having inputs that receive power from the battery in theportable computing device. But in some conditions it may be undesirableto provide power from the battery in the portable computing device. Forexample, when the portable computing device is receiving or providing asoftware or firmware update, its battery may be disconnected to avoiderrors that may occur due to a fault condition, such as a short circuitin a connection to an accessory. When the battery of the portablecomputing device is disconnected, the multiplexers may be powered by theaccessory.

An illustrative embodiment of the present invention may provide adocking station having a connector insert for mating with a receptacleon a smart phone or other portable computing device. The connectorinsert may be in a depression or well, the side or sides of which mayprovide mechanical support for an inserted smart phone or other portablecomputing device. The docking station may further include one or morereceptacles for communicating with one or more accessories, such asstorage devices, monitors, power supplies, adapters, and chargers, andother devices. In other embodiments, one or more receptacles may bereplaced with dedicated or tethered cables having a connector insert ata far end. These docking station connector inserts and receptacles maymate with connector receptacles or inserts for various interfaces suchas Universal Serial Bus (USB), High-Definition Multimedia Interface®(HDMI), Digital Visual Interface (DVI), power, Ethernet, DisplayPort,Thunderbolt™, Lightning™ and other types of standard and non-standardinterfaces.

Various embodiments of the present invention may incorporate one or moreof these and the other features described herein. A better understandingof the nature and advantages of the present invention may be gained byreference to the following detailed description and the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an electronic system that may be improved by theincorporation of an embodiment of the present invention;

FIG. 2 illustrates a docking station according to an embodiment of thepresent invention;

FIG. 3 illustrates a docking station according to an embodiment of thepresent invention;

FIG. 4 illustrates a docking station having a power switch according toan embodiment of the present invention;

FIG. 5 illustrates a docking station capable of providing power indifferent configurations to different accessories according to anembodiment of the present invention;

FIG. 6 illustrates a docking station including internal circuitryaccording to an embodiment of the present invention;

FIG. 7 illustrates a docking station including additional circuitryaccording to an embodiment of the present invention;

FIG. 8 illustrates a Lightning connector insert that may be employed andreceived by embodiments the present invention;

FIG. 9 illustrates a docking station including multiplexers and anassociated power circuit according to an embodiment of the presentinvention;

FIG. 10 illustrates a docking station according to an embodiment of thepresent invention; and

FIG. 11 illustrates a docking station having an alternate source ofpower for a circuit according to an embodiment of the present invention.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIG. 1 illustrates an electronic system that may be improved by theincorporation of an embodiment of the present invention. This figure, aswith the other included figures, is shown for illustrative purposes anddoes not limit either the possible embodiments of the present inventionor the claims.

This figure includes portable computing device or host 110, dockingstation or dock 120, and accessory device or accessory 130. Dockingstation 120 may provide mechanical support for portable computing device110. For example, docking station and 20 may have a connector insertthat may fit into a corresponding receptacle on portable computingdevice 110. This insert, along with one or more other supportstructures, may physically support portable computing device 110 indocking station 120. In other embodiments of the present invention,portable computing device 110 may connect to docking station 120 via acable, via a wireless connection, or combination thereof. Dockingstation 120 may further provide mechanical support for accessory 130.Again, docking station 120 may include a connector insert that may befitted into a receptacle on accessory 130. In other embodiments of thepresent invention, docking station 120 may include a receptacle formaking a connection to accessory 130 via a cable. In still otherembodiments of the present invention, docking station may include adedicated or tethered cable having an insert at a far end that may beinserted in a receptacle in an accessory. Docking station 120 maycommunicate with accessory 130 via one of these connections, a wirelessconnection, or combination thereof.

Data may be transferred between docking station 120 and portablecomputing device 110 via lines 114. Lines 114, as with the other linesshown, may be wired or wireless connections. Similarly, docking station120 may communicate with accessory 130 via data lines 124. Accessory 130may communicate through docking station 120 to portable computing device110 using lines 124 and 114.

Power may be shared among portable computing device 110, docking station120, and accessory 130 via lines 112 and 122, which again may be wiredor wireless connections. For example, portable computing device 110 mayinclude a battery that may provide power to docking station 120 andaccessory 130 via lines 112 and 122. Docking station 120 may include orreceive power, which may be provided to portable computing device 110over line 112 and to accessory 130 over line 122. Similarly, accessory130 may include or receive power, which it may provide to dockingstation 120 via line 122 and to portable computing device 110 via lines122 and 112. Power may be transferred between and among portablecomputing device 110, docking station 120, and one or more accessories130 using power conductors or other wired connections. Power may also betransferred between devices using wireless paths, for example by usinginductive or capacitive charging. In one specific embodiment of thepresent invention, docking station 120 may provide power to portablecomputing device 110 by inductive or capacitive charging. In anotherspecific embodiment of the present invention, docking station 120 mayprovide power to accessory 130 using inductive or capacitive charging,while in another, accessory 130 may provide power to docking station 120in a wireless manner.

While in this example, docking station 120 is shown as communicatingwith one accessory 130, in other embodiments of the present invention,docking station 120 may be configured to communicate with two or moreaccessories. Also, accessories 130 may be daisy-chained to communicatewith one or more other accessories, which are not shown for simplicity.

In various embodiments of the present invention, portable computingdevice 110 may be a smart phone, portable media player, laptop computer,tablet computer, navigational device, a wearable computing device suchas a bracelet or pendant, piece of clothing, or the like, or otherportable computing device. Accessory 130 may be a charger that receivespower from a wall or car outlet, speakers, computer, tablet, storagedevice, projector, camera, monitor, power supply, adapter, or otherdevice.

Again, embodiments of the present invention may provide docking stationsthat provide mechanical support for a portable computing device. Forexample, a docking station may include an insert that may be received bya receptacle on portable computing device. The docking station mayfurther include one or more receptacles or dedicated cables which may beused to connect to one or more accessories. These docking stations mayinclude one or more other features such as control buttons, displays, orother features. An example is shown in the following figure.

FIG. 2 illustrates a docking station according to an embodiment of thepresent invention. Docking station 120 may include connector insert 125for mating with receptacle 118 on smart phone or other portablecomputing device 110. Connector insert 125 may be located in adepression or well (not shown) that may provide mechanical support forsmart phone or other portable computing device 110. Connector insert 125may include a number of contacts to form power and signal paths withcorresponding contacts in connector receptacle 118. Docking station 120may further include one or more receptacles 128 and 129 forcommunicating with one or more accessories. In a specific embodiment ofthe present invention, receptacle 128 may be a lightning receptacle,while receptacle 129 may be a headphone jack.

Connector insert 125 may include contacts on one or more sides. Smartphone 110 may typically have contacts only on one side of receptacle 118in order to save space and to allow smart phone 110 to be thinner.Having contacts on two sides of connector insert 125 may allow smartphone 110 to be inserted in either of two ways in dock station 120. Tosimplify dock station 120, contacts may be removed or omitted on oneside of connector insert 125. In such an embodiment, smart phone 110 maybe inserted only one way on dock station 120. Docking station 120 may beshaped or formed such that smart phone or other portable computingdevice 110 may fit over connector insert 125 in the one properorientation to avoid consumer confusion.

Docking station 120 may include various additional components such aslight-emitting diodes (LEDs), buttons, touch pads, displays, wirelesscommunication devices, and other types of components.

For example, light-emitting diodes 123 may be used to indicate acharging status of a battery in a portable computing device 110. Amulti-colored LED may turn a first color to indicate that a charge isoccurring and a second color to indicate that charging is complete.Light-emitting diodes may also be used in conjunction with proximitysensors. Specifically, an LED may light when motion near connectorinsert 125 is detected. This illumination may assist a user in attachingportable computing device 110 to docking station 120, or it may assist auser in finding buttons, touch pads, or other controls on the dockingstation. Light-emitting diodes may also be used to indicate statussettings, such as do-not-disturb, airplane mode, and alarm statussettings.

Touch pads 121 or buttons 127 may be used to control playback volumethrough an audio channel. Touch pads 121 or buttons 127 may be used forsnooze or mode select functions, such as to put a portable computingdevice into a do-not-disturb or airplane mode.

Display 126 may be used to indicate time, mode of the device, weather,news, or other data. This data may be retrieved from an accessory orfrom portable computer device 110. Display 126 may be used to indicatean alarm or snooze setting, do-not-disturb or airplane settings, andother types of modes and settings.

Wireless communications devices (not shown) may be included in dockingstation 120 and used as remote controls for devices such as coffeemakers, thermostats, lighting, and other types of devices. The wirelesscommunication devices may also connect to cellular or Wi-Fi networks toretrieve, provide, or synchronize data.

Docking station 120 may also include gesture detection. Gesturedetection may allow a user to interact with docking station 120 bysimply making hand movements in the proximity of docking station 120.For example, a wave of a hand over docking station 120 may put an alarmin a snooze state. A gesture may be used to turn on a display, either onportable computing device 110 or docking station 120, to show time,date, weather, news, or other information or combination thereof. Whenviewing news on display 126, a gesture may be used to advance text to anext page. Other docking stations may include other features consistentwith embodiments of the present invention.

Again, embodiments of the present invention may provide docking stationsthat facilitate power transfer from an accessory to a portable computingdevice and from a portable computing device to an accessory. An exampleis shown in the following figure.

FIG. 3 illustrates a docking station according to an embodiment of thepresent invention. Docking station 120 may be housed in dockingenclosure 340. Docking enclosure 340 may include connector insert orplug 125 and receptacle 128. Two communication paths, DATA1 310 andDATA2 320 may connect to contacts in plug 125 and contacts in receptacle128. Data paths DATA1 310 and DATA2 320 may be single-ended ordifferential signal paths.

Other data, control, and power lines may be connected between plug 125and receptacle 128. One such control line may be an ID line 380. ID line380 may be used by an accessory connected to receptacle 128 to provideauthentication and identification information to a portable computingdevice connected to plug 125. More information on these and other dataand identification lines and related circuitry that may be included inembodiments of the present invention may be found in co-pending U.S.patent application Ser. No. 14/022,015, filed Sep. 9, 2013, titledDOCKING STATION WITH AUDIO OUTPUT, which is incorporated by reference.

Power on line 360, ACC power on line 370, as well as ground or otherpower or bias lines (not shown) may be provided between plug 125 andreceptacle 128. Specifically, power may be provided from an accessory130 over power line 360 to a portable computing device 110, or power maybe provided from the portable computing device 110 over ACC power line370 to an accessory 130.

In various embodiments of the present invention, receptacle 128 mayaccept different types of connector inserts. Some of these inserts maybe unidirectional, that is, a connector insert may be inserted intoreceptacle 128 in only one orientation. Examples of this type ofconnector include USB, HDMI, DVI, and Thunderbolt connectors. Each ofthe various docking stations shown in these examples may utilize thistype of connector to communicate with an accessory.

Other connector inserts may be bidirectional. That is, a connectorinsert may be inserted into receptacle 128 in at least two orientations.An example of this type of connector is the Lightening connector. ALightening connector may include eight contacts, where an order ofsignals, power, and communications signals may be one way if a connectorinsert is inserted into receptacle 128 with a first polarity, and theorder may be reversed if the connector inserted is inserted intoreceptacle 128 with a second or reversed polarity. Accordingly,circuitry associated with receptacle 128 may be used to detect aconnector insert orientation and reverse the signal order if a connectorinsert is inserted into receptacle 128 with the second or reversedpolarity. Details of how this reversal may be accomplished may be foundin co-pending U.S. patent application Ser. No. 13/607,550, filed Dec. 7,2012, titled TECHNIQUES FOR CONFIGURING CONTACTS OF A CONNECTOR, whichis incorporated by reference. Some of the various docking stationsherein or otherwise consistent with embodiments of the present inventionmay operate with this type of connector correctly if the portablecomputing device includes circuitry to adjust the order of the receivedsignals, control lines, and power supplies. Other examples includedocking stations that include circuits such that the docking station mayoperate with this type of connector, regardless of the capability of theportable computing device.

It should also be noted that some embodiments of the present inventionmay utilize a modified Lightening connector where the Lighteningconnector is unidirectional and can only be inserted into receptacle 128in one orientation. This may occur where a modified Lightening connectorhaving contacts only on one side of an insert is used. To avoidconfusion, this orientation may be indicated on the connector insert,for example with a symbol. This modified connector may operate with eachof the docking stations in these examples. The docking station in thisspecific example may operate with a unidirectional connector and aLightening or other bidirectional connector as receptacle 128 if theportable computing device includes circuitry to adjust the order of thereceived signals, control lines, and power supplies.

Similarly, plug 125 mat be a unidirectional or bidirectional connectorinsert. For example, plug 125 may be a unidirectional USB, HDMI, DVI, orThunderbolt connector, or a bidirectional connector such as a Lighteningconnector.

While in these examples a connection to a portable computing device isshown as plug 125 and a connection to an accessory is shown asreceptacle 128, in other embodiments of the present invention plug 125may be replaced by a receptacle and receptacle 128 may be replaced by aplug, such as a plug connected to docking station 120 via a cable.

In the above example, POWER 360 and other bias lines may be coupledbetween plug 125 and receptacle 128. But this may cause voltages to bepresent on exposed contacts on plug 125 when a portable computing deviceis not attached to docking station 120. Accordingly, embodiments of thepresent invention may provide one or more switches, relays, variableresistances, or other mechanism to avoid exposing such voltages wherethey may be inadvertently contacted by a user or the user's property. Anexample is shown in the following figure.

FIG. 4 illustrates a docking station having a power switch according toan embodiment of the present invention. In this example, power switch410 may be included. In this and the following examples, lines such asdata and identification lines are omitted for clarity. Power switch 410may receive power from an accessory on line 420, such as a charger, viareceptacle 128. Power switch 410 may detect or be informed whether aportable computing device 110 is attached at plug 125. If no portablecomputing device 110 is attached at plug 125, power switch 410 may be inan open or high-impedance state, thereby protecting a user frominadvertent contact with a voltage on an exposed contact on plug 125.Power switch 410 may provide protection by being open, such that novoltage is present at plug 125. Power switch 410 may also be in asufficiently high-impedance state such that a voltage at plug 125 iscurrent limited enough that harm from an inadvertent encounter is notlikely. When a portable computing device 110 is attached at plug 125,power switch 410 may be in a closed or low-impedance state, and powermay be provided by accessory 130 onto line 420, through power switch 410and power line 360 to plug 125, where it may be received by portablecomputing device 110.

In a specific embodiment of the present invention, power switch 410 mayinclude circuitry to sense an impedance at a pin at plug 125 in order todetermine that portable computing device 110 is attached at plug 125,though this determination may be made by power switch 410 in other ways.In other embodiments of the present invention, other circuits may detectthat computing device 110 is attached at plug 125 by looking for aconnection to ground at one pin, or by using another method. This othercircuit may then inform power switch 410 that computing device 110 isattached at plug 125. In still other embodiments of the presentinvention, power switch 410 may itself have this capability.

In the above examples, power may be provided directly from portablecomputing device 110 to accessory 130. In other embodiments of thepresent invention, this direction connection may be absent or limited toa number of situations. An example is shown in the following figure.

FIG. 5 illustrates a docking station capable of providing power indifferent configurations to different accessories according to anembodiment of the present invention. In this example, power may beprovided by docking station 120 to accessory 130 in two differentconfigurations. In a first configuration, switch 520 may be closed andlow-dropout regulator 530 may be disabled. ACC power received on line370 from portable computing device 110 via plug 125 may be passedthrough switch 520 to line ACC OUT 550. Power on line ACC OUT 550 may beprovided through receptacle 128 to accessory 130.

In this configuration, accessory 130 may have direct access to a batteryon portable computing device 110. Unfortunately, accessories, such asaccessory 130, may occasionally create a fault condition, such as apower supply short. Accordingly, switch 520 may be current limited orcontain other protections for the battery in portable computing device110.

In various embodiments of the present invention, this direct or neardirect access may be limited to specific accessories 130. For example,specific types of accessories may be granted access to a battery inportable computing device 110 via switch 520, or access may be limitedto accessories that have undergone certain testing or qualifications. Inother embodiments of the present invention, accessories manufactured byspecific vendors or suppliers may have access to a battery in portablecomputing devices 110 via switch 520, while in other embodiments of thepresent invention, this access may be granted to accessories using othercriterion or criteria.

When direct access to the battery in portable computing device 110 isdesired to be further limited, a second configuration may be included indocking station 120. In this example, low-dropout regulator 530 may beincluded. When accessory 130 does not meet the specified criterion orcriteria, power may be provided to the accessory on line ACC OUT 550 bylow-dropout regulator 530. Low-dropout regulator 530 may have an inputconnected directly through line ACC POWER 370 to a battery in portablecomputing device 110. In other embodiments of the present invention, aregulator, such as buck-boost regulator 510, may be provided such thatlow-dropout regulator 530 may have a well-regulated input voltage.

In this way, power in one of two configurations may be provided toaccessory, though other configurations may be included as well. Also,various embodiments of the present invention may employ one or the otherabove configurations for all accessories, and may not include the unusedconfiguration. Trusted accessories may receive a direct or near directconnection to a battery in portable computing device 110. This may allowa trusted accessory to have access to a great deal of power for fastcharging or other high power applications. Other accessories may belimited to the power that low-dropout regulator 530 may provide.However, this lower power output may have improved voltage regulationdue to the inclusion of a regulator, such as buck-boost regulator 510,and the additional regulation provided by low-dropout regulator 530. Inother embodiments of the present invention, buck-boost regulator 510 maybe another type of regulator, such as a shunt regulator, whilelow-dropout regulator 530 may be another type of DC-to-DC converter orregulator.

Embodiments of the present invention may provide docking stations thatmay include various circuits. In these embodiments, docking stationcircuits may be powered either from portable computing device 110,accessory 130, or by other circuitry other internal or external todocking station 120. An example is shown in the following figure.

FIG. 6 illustrates a docking station including internal circuitryaccording to an embodiment of the present invention. This exampleincludes a microprocessor or microcontroller 620. Microprocessor 620 maybe powered by low-dropout regulator 610. Low-dropout regulator 610 mayreceive its power from portable computing device 110 via plug 125 andline ACC POWER 370, though in other embodiments of the presentinvention, low-dropout regulator 610 may receive power from linecharging power on line 420, or from a power circuit that is internal orexternal to docking station 120. For example, docking station 120 mayinclude transformers, capacitors, and other components needed to convertAC power to DC power that may be provided to circuits in and associatedwith docking station 120. While regulator 610 is shown in this exampleas a low-dropout regulator, in other embodiments of the presentinvention low-dropout regulator 610, as with the other includedlow-dropout regulators, may be other types of DC-to-DC converters orregulators.

Again, accessory 130 may create a fault condition on line ACC OUT 550,or another fault condition may occur. This fault condition may cause thevoltage on line ACC POWER 370 to drop. Such a drop may erase or resetthe contents of microprocessor 620. To keep this from happening,embodiments the present invention may provide charge capacitors tomaintain an input voltage at regulators or other circuits during such atransient fault condition. In this example, capacitor C1 may be includedat an input of low-dropout regulator 610. Disconnect diode D1 mayprovide a high-impedance path back into ACC POWER 370 when a faultcondition occurs, thereby maintaining a charge on capacitor C1.

In various embodiments of the present invention, other circuitry may beincluded in docking station 120. Such circuits may be powered bylow-dropout regulator 610, or they may be powered by other regulatingcircuits.

In various embodiments of the present invention, various circuits may bedisabled when they are not being used in order to save power.Accordingly, various regulators may be disabled, thereby removing powerfrom their associated circuits. Also, these regulators may be powered byvarious sources, such as a battery in portable computing device 110 viaACC POWER 370, or by another regulator, such as buck-boost regulator510. An example is shown in the following figure.

FIG. 7 illustrates a docking station including additional circuitryaccording to an embodiment of the present invention. In this example,bridge circuit 730, digital-to-analog converter 740, audio oscillator750, and authentication circuit 760 may be included. On occasion, thesevarious circuits may not be needed. For example, once docking station120 is authenticated to portable computing device 110, authenticationcircuit 760 may be shut off. Accordingly, low-dropout regulator 720,which powers authentication circuit 760, may be disabled by a signal onEN2 720. Similarly, when no audio signal is being generated, at leastpart of digital-to-analog converter 740 may be shut off by disablinglow-dropout regulator 720 using signal EN1 715.

In this example, low-dropout regulator 710 may power digital-to-analogconverter 740. Digital-to-analog converter 740 may be used in dockingstation 120 to generate an audio signal. Since the quality of an audiosignal is important, low-dropout regulator 710 may be powered bybuck-boost regulator 510. The cleaner supply voltage provided bybuck-boost regulator 510 may help to improve audio quality provided bydocking station 120. Further examples of the functions performed bymicroprocessor 620, bridge 730, digital to analog converter 740,oscillator 750, authentication circuit 760, and other circuits (notshown), may be found in co-pending U.S. patent application Ser. No.14/022,015, filed Sep. 9, 2013, titled DOCKING STATION WITH AUDIOOUTPUT, which is incorporated by reference.

Embodiments of the present invention may communicate with one or moreaccessories and portable computing devices using different types ofconnector interfaces. One such interface is the Lightning connectorinterface. Lightning connectors are reversible. That is, a Lightningconnector insert may be inserted into a Lightening receptacle in one oftwo orientations. Accordingly, embodiments of the present invention mayinclude a number of multiplexers to multiplex signals received from anaccessory. An example of a Lightning connector insert is shown in thefollowing figure.

FIG. 8 illustrates a Lightning connector insert that may be employed andreceived by embodiments the present invention. Specifically, thisconnector may be used as connector 125 on docking station 120. It mayalso be used as a plug attached to a cable to replace receptacle 128 asa way to connect to an accessory. This connector may also be received atreceptacle 128 in some of the examples shown herein.

Connector insert 125 may include insert portion or tab 802. Tab 802 maybe sized to be inserted into a corresponding receptacle connector duringa mating event and may include a first contact region 806 formed on afirst major surface 804 and a second contact region (not shown) formedat a second major surface (also not shown) opposite surface 804. Surface804 may extend from a distal tip 814 of tab 802 to spine 816 that, whentab 802 is inserted into a corresponding receptacle connector, abuts ahousing of the receptacle connector or portable computing device thatthe receptacle connector is incorporated in. Tab 802 may also includefirst and second opposing side surfaces that extend between the firstand second major surfaces including 804.

A plurality of contacts 810 can be formed in each of contact regions 806on each side of tab 802 such that, when tab 802 is inserted into acorresponding receptacle connector, contacts 806 are electricallycoupled to corresponding contacts in the receptacle connector. In someembodiments, contacts 806 are self-cleaning wiping contacts that, afterinitially coming into contact with a receptacle connector contact duringa mating event, slide further past the receptacle connector contact witha wiping motion before reaching a final, desired contact position.

The structure and shape of tab 802 may be defined by a ground ring 808that can be made from stainless steel or another hard conductivematerial. Connector 125 may include retention feature 812 and acorresponding feature on the opposite side of tab 802 formed as curvedpockets in the sides of ground ring 808 that may double as groundcontacts.

Various embodiments of the present invention may utilize this or othertypes of connectors as plug 125 on docking station 120, as plug 544 toconnect to an accessory, or to be accepted at receptacle 128 by dockingstation 120. The numbers pins or contacts and pins assignments may varyas well. Specific pinouts that may be used for these plugs andreceptacles can be found in co-pending U.S. patent application Ser. No.13/607,366, filed Sep. 7, 2012, titled DUAL ORIENTATION ELECTRONICCONNECTOR, which is incorporated by reference.

Again, this connector may be used as connector 125 on docking station120. It may also be used as plug 544 attached to cable 542 in thetethered cable examples shown herein. This connector may also bereceived at receptacle 128 in the following figures. (It may also bereceived in the examples above, but care should be taken to ensure thatonly an insertion that does not require an inversion or reversal ismade. This may be accomplished, for example, by using a cable having amarking to indicate a desirable orientation.)

Again, using these connectors in a docking station with a multiplexingcircuit may allow a connector to be inserted in either of at least twoorientations in receptacle 128. As with microprocessor 620 and othercircuits described above, these multiplexers may be powered by eitherportable computing device 110, accessory 130, or by other circuitryassociated with docking station 120. An example is shown in thefollowing figure.

FIG. 9 illustrates a docking station including multiplexers and anassociated power circuit according to an embodiment of the presentinvention. In this example, multiplexers 940 are included. Again, thesemultiplexers may enable the use of a reversible connector at receptacle128. In other embodiments of the present invention, receptacle 128 maybe replaced by a cable and a plug that is reversible.

Multiplexers 940 may be powered by low-dropout regulators 910 and 920.These low-dropout regulators may provide different voltages to differentparts of multiplexers 940. Low-dropout regulators 910 and 920 mayreceive power from portable computing devices 110 via plug 125 and ACCPOWER 370. Resistor R1 and capacitor C2 may help smooth noise andtransients caused by fault conditions, such as power supply shorts online ACC OUT 550. Multiplexers 940 may be disabled using line EN3 945.Specifically, an open drain device may be connected to line EN3 945.When this open drain device is active, current may flow through resistorR2, pulling EN3 945 to ground.

In this example, multiplexers 940 may receive a supply voltage at inputVDD2 from low-dropout regulator 920. Low-dropout regulator 920 may bepowered by a voltage on line ACC power 370. This voltage, which may beprovided by a battery in portable computing device 110, may beinsufficient to provide a desirable voltage on line VDD2. Accordingly,embodiments of the present invention may provide a second regulator toprovide sufficient voltage when a first regulator powered by a batteryin portable computing device 110 is unable. An example is shown in thefollowing figure.

FIG. 10 illustrates a docking station according to an embodiment of thepresent invention. In this example, low-dropout regulator 1010 has beenadded. Low-dropout regulator 1010 may be driven by buck-boost regulator510. Buck-boost regulator 510 may provide sufficient voltage tolow-dropout regulator 1010 such that it may in turn provide sufficientvoltage to multiplexing circuitry 940 on line VDD2 even when the voltageon line ACC POWER 370 is insufficient.

Specifically, buck-boost regulator 510 may boost voltage received on ACCPOWER 370. This boosted voltage may be regulated by low-dropoutregulator 1010. Disconnect diode D2 may couple low-dropout regulator1010 to voltage terminal VDD2 when the output of low-dropout regulator1010 is higher than the output of low-dropout regulator 910.Accordingly, when a voltage on line ACC POWER 370 is low, such that theoutput of low-dropout regulator 920 is low, the output of low-dropoutregulator 1010 may provide a sufficient voltage to input VDD2 to amultiplexing circuit 940 via diode D2.

In various embodiments of the present invention, diodes, such as diodeD1, D2, D3, and D4, may be Schottky diodes, though in other embodimentsof the present invention they may be other types of diodes. These diodesmay provide a voltage drop on the order of opening 0.3 Volts. That is, avoltage received at input VDD2 to multiplexing circuit 940 may be 0.3Volts lower than a voltage provided at the output of low-dropoutregulator 1010. Also, a various embodiments of the present invention,each of the various included regulators may provide a fixed nominaloutput voltage. This fixed nominal output voltage may be different fordifferent regulators, though different regulators may share the samenominal output voltage. For example, they may have output voltages thatare one of 1.8 Volts, 3.1 Volts, 3.3 Volts, 3.6 Volts, or othervoltages. In a various embodiments of the present invention, regulators610, 720, and 910 may nominally provide one of 1.8 Volts, 3.1 Volts, or3.3 Volts, regulator 710 may provide one of 1.8 Volts, 3.1 Volts, or 3.3Volts, while regulators 530, 920, and 1010 may provide one of 1.8 Volts,3.1 Volts, or 3.3 Volts. In various embodiments of the presentinvention, Buck-Boost regulator 510 may provide one of 3.1 Volts, 3.3Volts, or 3.6 Volts. In still other embodiments of the presentinvention, these and other regulators may provide different voltages.These fixed output voltages may have different tolerances.

In various embodiments of the present invention, software and firmwareupdates and other data transfers may be provided by a computer connectedas accessory 130 to portable computing device 110 via a docking station120. Again, various fault conditions may cause the voltage on line ACCPOWER 370 to dip considerably, at least in a transient manner. Since ACCPOWER 370 may be directly connected to a battery in portable computingdevice 110, such a fault conditions may also cause supply voltages inportable computing device 110 to drop in a transient manner. This may beparticularly unfortunate when a software or firmware update is occurringas this may cause instability in the operation of portable computingdevice 110. Accordingly, portable computing device 110 may remove poweron line ACC POWER 370 in order to protect its battery.

This removal of power may in turn remove power from multiplexers 940.But this in turn may disconnect data paths that extend from accessory130 through receptacle 128 and multiplexers 940 to plug 125 and portablecomputing device 110. Accordingly, embodiments of the present inventionmay provide an alternate power source for multiplexers 940. An exampleis shown in the following figure.

FIG. 11 illustrates a docking station having an alternate source ofpower for a circuit according to an embodiment of the present invention.In this example, the circuit is multiplexing circuit 940. Power may beprovided to low-dropout regulators 910 and 920 by either a voltage online ACC POWER 370 or a voltage on line CHARGING POWER 420. Disconnectdiodes D3 and D4 may act as an “OR” function providing the highervoltage to the inputs of low-dropout regulators 910 and 920 via resistorR1. In this way, the voltage on line CHARGING POWER 420 may powerlow-dropout regulators 910 and 920 via resistor R1 and D3 when ACC POWER370 is absent, due to an update of for other reason. This may ensurethat multiplexers 940 remaining configured during a software or firmwareupdate of portable computing device 110.

Again, receptacle 128 may receive a Lightning connector insert. When aLightning connector insert is disconnected from receptacle 128, voltagesat its contacts may be disabled or in a high impedance state. Thesevoltages may remain in this state until the connector insert isinitially inserted into receptacle 128. Drawing current when a supply isin a high impedance state may cause the supply voltage to drop to nearzero. Accordingly, it is undesirable at this time to draw current fromline CHARGING POWER 420 via low-dropout regulators 910 and 920.Accordingly, embodiments the present invention may include a switch,such as transistor M1, that may be open until a connector insert atreceptacle 128 exits its high impedance state.

Specifically, when the voltage supplies on a connector insert atreceptacle 120 are in high-impedance state, very little power isavailable to docking station 120. Accordingly, transistor M1 may be openand power draw may be essentially limited to establishing identificationand authentication over ID line or bus 925 using ID control circuit 930.Once this identification and authentication handshaking is completed,the connector insert at receptacle 128 may exit its high-impedance stateand provide full power on line CHARGING POWER 420. In this situation,transistor M1 may close such that a voltage on CHARGING POWER 420 mayprovide power to low-dropout regulators 910 and 920 as needed.

Again, in this embodiment of the present invention, the higher of eithera voltage on CHARGING POWER 420 or ACC POWER 370 may be provided throughdiodes D3 and D4 to low-dropout regulators 910 and 920. In otherembodiments of the present invention, transistor M1 may be open suchthat power is not drawn from accessory 930 whenever power is availablefrom the portable computing device 110 on line ACC POWER 370. In stillother embodiments of the present invention, when portable computingdevice 110 is not connected to plug 125, transistor M1 may be open sincethere is no need at that time to provide power to low-dropout regulators910 and 920. While in these examples M1 is opened to disconnect CHARGINGPOWER 420 from low-dropout regulators 910 and 920, in other embodimentsof the present invention, other devices, switches, circuits, or othercomponents may be used to disconnect this path. For example, the ENinputs to low-dropout regulators 910 and 920 may be modified to acceptan input that disables them in this condition.

The above description of embodiments of the invention has been presentedfor the purposes of illustration and description. It is not intended tobe exhaustive or to limit the invention to the precise form described,and many modifications and variations are possible in light of theteaching above. The embodiments were chosen and described in order tobest explain the principles of the invention and its practicalapplications to thereby enable others skilled in the art to best utilizethe invention in various embodiments and with various modifications asare suited to the particular use contemplated. Thus, it will beappreciated that the invention is intended to cover all modificationsand equivalents within the scope of the following claims.

What is claimed is:
 1. A docking station comprising: a housing; aconnector insert located on the housing and arranged to mate with aconnector receptacle on a portable computing device; a second connectorto connect to an accessory; a first regulator having an input coupled tothe connector insert to receive power from the portable computingdevice, the first regulator further having an output coupled to thesecond connector to provide power to a first type of accessory; and afirst switch having an input coupled to the connector insert to receivepower from the portable computing device and having an output coupled tothe second connector to provide power to a second type of accessory. 2.The docking station of claim 1 further comprising a second regulator topower a microprocessor, a diode between the first connector and an inputof the second regulator, and a capacitor between the input of the secondregulator and ground.
 3. The docking station of claim 2 wherein an anodeof the diode is coupled to the first connector and a cathode of thediode is coupled to the input of the second regulator.
 4. The dockingstation of claim 1 wherein the input of the first switch is coupled tothe input of the first regulator and the output of the first switch iscoupled to the output of the first regulator.
 5. The docking station ofclaim 4 wherein the first regulator is a low-dropout regulator.
 6. Thedocking station of claim 5 further comprising a second regulator coupledbetween the connector insert and the first regulator.
 7. The dockingstation of claim 6 wherein the second regulator is a buck-boostregulator.
 8. The docking station of claim 7 wherein the connectorinsert is a Lightening connector insert.
 9. The docking station of claim7 wherein the portable computing device comprises a smart phone.
 10. Thedocking station of claim 7 wherein a second type of accessory is anaccessory having a first voltage requirement.
 11. The docking station ofclaim 7 wherein a second type of accessory is an accessory made by aspecific vendor.
 12. The docking station of claim 7 wherein the secondconnector is located on the housing and comprises a connectorreceptacle.
 13. The docking station of claim 7 wherein the secondconnector comprises a connector insert and the connector insert connectsto the docking station via a cable.
 14. The docking station of claim 1wherein the input of the first switch is coupled to the input of thefirst regulator and the output of the first switch is directly connectedto the output of the first regulator.
 15. The docking station of claim 1further comprising: a first circuit; and a power circuit to providepower to the first circuit from either the portable computing device oran accessory in a first mode, and to provide power to the first circuitfrom an accessory in a second mode, wherein in the first mode, the powercircuit provides power to the first circuit from the portable computingdevice when a voltage provided by the portable computing device ishigher than a voltage provided by the accessory, and the power circuitprovides power to the first circuit from the accessory when a voltageprovided by portable computing device is lower than a voltage providedby the accessory.
 16. The docking station of claim 15 wherein the firstcircuit comprises a multiplexing circuit.
 17. The docking station ofclaim 16 wherein the multiplexing circuit multiplexes signals at thesecond connector such that the second connector may be reversible. 18.The docking station of claim 15 wherein the second mode is a programmingmode for the portable computing device.
 19. The docking station of claim15 wherein the power circuit comprises a second regulator coupled to theconnector insert and further coupled to the second connector.
 20. Thedocking station of claim 19 wherein the second regulator comprises alow-dropout regulator.
 21. The docking station of claim 20 wherein thepower circuit further comprises a first disconnect diode between theconnector insert and the power circuit and a second disconnect diodebetween the second connector and the power circuit.
 22. The dockingstation of claim 21 further comprising an resistor in series between thefirst and second disconnect diodes and an input of the power circuit,and a first capacitor between the input of the power circuit and ground.23. The docking station of claim 22 further comprising a second switchbetween the second disconnect diode and the second connector.
 24. Thedocking station of claim 23 wherein the power circuit further comprisesa third regulator having an input coupled to the input of the secondregulator.
 25. The docking station of claim 24 further comprising: afourth regulator having an input coupled to the input of the firstregulator; a third disconnect diode coupled between an output of thefourth regulator and an output of the third regulator; and a secondcapacitor coupled between the output of the third regulator and ground.26. The docking station of claim 15 wherein the second connector islocated on the housing and comprises a connector receptacle.
 27. Thedocking station of claim 15 wherein the second connector comprises aconnector insert and the connector insert connects to the dockingstation via a cable.
 28. The docking station of claim 15 wherein thepower from the portable computing device is provided by a battery on theportable computing device.
 29. The docking station of claim 1 whereinthe first switch is current limited.